Bamako , Mali -LRB- CNN -RRB- -- Malian authorities have found a mass grave containing 21 bodies thought to be soldiers killed while a junta chief was in power after a 2012 military coup , a Ministry of Defense spokeswoman said Wednesday .

Investigators found the bodies in a grave close to a military camp in the village of Diago , just north of Bamako , spokeswoman Alasane Diarra said .

Last week , Gen. Amadou Sanogo , who led the March 2012 coup , was arrested , charged with complicity in kidnapping .

A failed counter-coup shortly after he seized power pitted two army factions against each other : the green berets loyal to Sanogo and the red berets loyal to ousted President Amadou Toumani Toure .

`` At the military camp in Diago , there were both green berets and red berets soldiers . We do not know which group the soldiers in the grave belonged to , '' Diarra said .

Investigations into alleged kidnapping and killings after the military takeover that plunged the West African country into chaos have been ongoing since April 30 , 2012 .

`` The investigators have been working on the case since April , so just after the coup . They have known about the grave for a while , but when they finally went there and opened the grave , there were more bodies than they previously thought , '' Diarra said .

The bodies are all male and from different ethnic groups , she said .

As the bodies are removed from the grave , forensic investigators will start the process of identifying the men .

`` Families of soldiers who disappeared during the coup will be asked to come and identify their family members , '' Diarra said .

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The bodies are thought to be those of soldiers , a Ministry of Defense spokeswoman says

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They are believed to have been killed after Mali 's March 2012 coup

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Investigators will seek to identify the men as they are removed from the mass grave

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Coup leader Amadou Sanogo has been arrested , accused of complicity in kidnapping